Suspected gang members in Mexico have confessed to killing more than 40 missing students and incinerating their remains.
However, Attorney General Jesus Murillo Karam warned that it would be difficult to identify the charred remains.
Authorities will continue to consider the students as missing until DNA tests confirm the identities.
Searches for the 43 students have been taking place since police attacked their buses in the southern city of Iguala on 26 September.
The attacks were carried out allegedly under orders of the mayor and his wife in violence that also left six people dead.
The three suspects said the students were killed after they were handed over to them between Iguala and the neighbouring town of Cocula by police linked to the Guerreros Unidos drug gang, Murillo Karam said.
The bodies were set on fire with petrol, tires, firewood and plastic in an inferno that lasted 14 hours, he said.
"The fire lasted from midnight to 2pm the next day. The criminals could not handle the bodies (for three hours) due to the heat," he said.
The suspects then crushed the remains, stuffed them in bags and threw them in a river.
The suspects were not sure how many students they received but one of them said there were more than 40.
Before the announcement, relatives of the missing said they would not accept that their children were killed until they get the results of independent Argentine forensic experts.
